Measuring whole plant CO2 exchange with the environment reveals opposing effects of the gin2–1 mutation in shoots and roots of <i>Arabidopsis thaliana</i>
Using a cuvette for simultaneous measurement of net photosynthesis in above ground plant organs and root respiration we investigated the effect of reduced leaf glucokinase activity on plant carbon balance. The gin2–1 mutant of Arabidopsis thaliana is characterized by a 50\% reduction of glucokinase activity in the shoot, while activity in roots is about fivefold higher and similar to wild type plants. High levels of sucrose accumulating in leaves during the light period correlated with elevated root respiration in gin2–1. Despite substantial respiratory losses in roots, growth retardation was moderate, probably because photosynthetic carbon fixation was simultaneously elevated in gin2–1. Our data indicate that futile cycling of sucrose in shoots exerts a reduction on net CO2 gain, but this is over-compensated by the prevention of exaggerated root respiration resulting from high sucrose concentration in leaf tissue.
%0 Journal Article
%1 Brauner2015
%A Brauner, Katrin
%A Stutz, Simon
%A Paul, Martin
%A Heyer, Arnd G
%D 2015
%J Plant Signaling Behav.
%K brauner metabolism myown paul stutz
%N 1
%P e973822
%R 10.4161/15592324.2014.973822
%T Measuring whole plant CO2 exchange with the environment reveals opposing effects of the gin2–1 mutation in shoots and roots of <i>Arabidopsis thaliana</i>
%U http://dx.doi.org/10.4161/15592324.2014.973822
%V 10
%X Using a cuvette for simultaneous measurement of net photosynthesis in above ground plant organs and root respiration we investigated the effect of reduced leaf glucokinase activity on plant carbon balance. The gin2–1 mutant of Arabidopsis thaliana is characterized by a 50\% reduction of glucokinase activity in the shoot, while activity in roots is about fivefold higher and similar to wild type plants. High levels of sucrose accumulating in leaves during the light period correlated with elevated root respiration in gin2–1. Despite substantial respiratory losses in roots, growth retardation was moderate, probably because photosynthetic carbon fixation was simultaneously elevated in gin2–1. Our data indicate that futile cycling of sucrose in shoots exerts a reduction on net CO2 gain, but this is over-compensated by the prevention of exaggerated root respiration resulting from high sucrose concentration in leaf tissue.
@article{Brauner2015,
abstract = { Using a cuvette for simultaneous measurement of net photosynthesis in above ground plant organs and root respiration we investigated the effect of reduced leaf glucokinase activity on plant carbon balance. The gin2–1 mutant of Arabidopsis thaliana is characterized by a 50\% reduction of glucokinase activity in the shoot, while activity in roots is about fivefold higher and similar to wild type plants. High levels of sucrose accumulating in leaves during the light period correlated with elevated root respiration in gin2–1. Despite substantial respiratory losses in roots, growth retardation was moderate, probably because photosynthetic carbon fixation was simultaneously elevated in gin2–1. Our data indicate that futile cycling of sucrose in shoots exerts a reduction on net CO2 gain, but this is over-compensated by the prevention of exaggerated root respiration resulting from high sucrose concentration in leaf tissue. },
added-at = {2018-09-06T15:28:49.000+0200},
author = {Brauner, Katrin and Stutz, Simon and Paul, Martin and Heyer, Arnd G},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2628eac7dc32b4ac6cc7fbb6dbae9165a/arndheyer},
doi = {10.4161/15592324.2014.973822},
eprint = {http://dx.doi.org/10.4161/15592324.2014.973822},
interhash = {bdd0a838edda2e3716b78719bb5e89f8},
intrahash = {628eac7dc32b4ac6cc7fbb6dbae9165a},
journal = {Plant Signaling Behav.},
keywords = {brauner metabolism myown paul stutz},
note = {PMID: 25482780},
number = 1,
pages = {e973822},
timestamp = {2018-09-13T18:20:46.000+0200},
title = {Measuring whole plant CO2 exchange with the environment reveals opposing effects of the gin2–1 mutation in shoots and roots of <i>Arabidopsis thaliana</i>},
url = {http://dx.doi.org/10.4161/15592324.2014.973822 },
volume = 10,
year = 2015
}